-LRB- CNN -RRB- -- A top judge has issued a special plea to the four suspects named in the killing of former Lebanese Prime Minister Rafik Hariri killing to come before the court .

Judge Antonio Cassese , the president of the Special Tribunal for Lebanon , said in an open letter to the four men accused in the 2005 attack that they will be treated fairly if they appear before the court or even participate in the trial proceedings without being present .

Cassese issued the statement after Lebanese authorities told him they have been unable so far to serve warrants on and arrest the accused .

`` We will conduct trials based on a firm presumption of innocence of the accused . The Tribunal shall never convict anybody unless guilt is established beyond any reasonable doubt , '' he said .

Arrest warrants were issued for Salim Jamil Ayyash , Mustafa Amine Badreddine , Hussein Hassan Oneissi , and Assad Hassan Sabra .

A highly placed source in the Lebanese army , who had correctly given CNN the names of the suspects previously , has said that all four belong to Hezbollah , the Lebanese Shiite militant group .

Hariri , a wealthy entrepreneur turned politician , died when his motorcade was hit by a bomb in Beirut on February 14 , 2005 .

Supporters say he was killed because of his opposition to Syrian influence in Lebanon . His death prompted mass protests that led to the withdrawal of Syrian troops from Lebanon , who had been in the country for nearly 30 years .

Cassese defended the tribunal , saying its personnel `` are doing their job with full independence and impartiality . ''

`` We are only acting in the interest of Lebanon ; our only motivation is the pursuit of justice . Our exclusive aim is to find the truth about the assassination of 14 February 2005 and other possibly connected criminal cases , while upholding the highest international standards of criminal law . ''

The judge said that if the accused do n't wish to come before the tribunal at The Hague in the Netherlands , they can participate by video link .

Cassese said the tribunal `` will appoint the best professionals to represent them in court '' in their absence .

But he urged them to appoint legal counsel and pass along instructions to them , even if they choose not to appear before the court .

`` If you believe this Tribunal is illegal or illegitimate , argue this point through legal counsel chosen by you -- you will thus have your voice heard on this issue . Use your counsel to make your case and zealously protect your rights . ''

If they ca n't afford lawyers , tribunal funds are available for hiring legal counsel .

`` The march to justice is inexorable , and one way or another we will end up with a trial . I therefore strongly appeal to the accused to take advantage of the broad legal possibilities offered by our Rules of Procedure and Evidence , thereby contributing to the establishment of truth and the conduct of fair proceedings , '' he said .

As for Lebanese authorities , the judge said he 's hopeful they will `` persist in their search for the accused . ''

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The four suspects are said to be members of Hezbollah

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Rafik Hariri was assassinated February 14 , 2005 , in Beirut

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Lebanese authorities say they ca n't get their hands on the suspects